The present invention is concerned with a method for the treatment of irritable bowel syndrome which involves the multiple daily dosing of an immediate release formulation of the anti-muscarinic darifenacin. Dosing two or three times a day is particularly preferred.
Darifenacin is a muscarinic antagonist whose preparation and proposed use in the treatment of diseases associated with altered motility and/or tone of smooth muscle as found, for example, in the gut, trachea and bladder are described in U.S. Pat. No. 5,096,890. Specific diseases referred to include irritable bowel syndrome, diverticular disease, urinary incontinence, oesophageal achalasia and chronic obstructive airways disease. Of these, irritable bowel syndrome and urinary incontinence are particularly attractive targets for a muscarinic antagonist and controlled release formulations of darifenacin intended for use in the treatment of these diseases wherein at least 10% by weight of the darifenacin is released in the lower gastrointestinal tract are the subject of U.S. Pat. No. 6,106,864.
The text of these patents and all other references cited in this specification are hereby incorporated by reference in their entirety.
In one aspect, the invention is directed to a method for treating irritable bowel syndrome comprising a multiple daily pulse dosing of a darifenacin immediate release dosage form.
In a preferred embodiment, the immediate release dosage form is administered three times a day.
In another preferred embodiment, the immediate release dosage form is administered at about 8-hourly intervals.
In an other preferred embodiment, the immediate release dosage form is administered two times a day.
In a further preferred embodiment, the dosage form is administered at about 12-hourly intervals.
In an other preferred embodiment, the the immediate dosage form is administered prior to eating.
In a preferred embodiment, the dosage form is an immediate release tablet, capsule, liquid, or fast-dispersing or fast-dissolving dosage form or a form suitable for nasal or inhaled administration.
In a further preferred embodiment, the dosage form is an immediate release tablet or capsule.
In a preferred embodiment, the tablet or capsule contains approximately 2.5 mg of darifenacin.
In a preferred embodiment, the method is used for the treatment of constipated patients.
In an other preferred embodiment, the tablet or capsule contains approximately 5.0 mg or approximately 7.5 mg of darifenacin.
In a preferred embodiment, the method is used for the treatment of diarrhoea-predominant patients.
In a preferred embodiment, the plasma concentration of darifenacin exceeds that obtainable by controlled release medication at least twice a day.
In an other preferred embodiment, the plasma concentration of darifenacin exceeds that obtainable by controlled release medication three times a day.
In an other preferred embodiment, the plasma concentration of darifenacin exceeds that obtainable by controlled release medication twice a day.
In a preferred embodiment, the plasma concentration of darifenacin declines to less than 50% of its maximum value after 4 hours.